DE102021202914B3 - Pulse-controlled inverter arrangement and method for operating a pulse-controlled inverter arrangement - Google Patents

Abstract

The invention relates to a pulse-controlled inverter arrangement (1), comprising a positive high-voltage input (2+) for supplying a positive line (3+), a negative high-voltage input (2-) for supplying a negative line (3-), a pulse-controlled inverter (4) for providing at least an AC voltage from a DC voltage provided via the lines (3+,3-), at least one resistor arrangement (6) between the plus line (3+) and the minus line (3-) with at least one resistor (Rx), the at least one resistor arrangement (6) has at least one self-conducting semiconductor switch (7) which is set up and arranged in such a way as to close or close an electrical connection established via the at least one resistor arrangement (6) between the positive line (3+) and the negative line (3-). separate, and a control device (8), wherein the control device (8) is set up, at least in a normal operating state, the at least ens to turn off a normally on semiconductor switch (7). The invention also relates to a method for operating a pulse-controlled inverter arrangement (1).

Description

The invention relates to a pulse-controlled inverter arrangement and a method for operating a pulse-controlled inverter arrangement.

In vehicles, in particular electric vehicles, a resistor chain is installed in parallel with a pulse-controlled inverter. The aim of the resistor chain is to discharge an upstream intermediate circuit capacitor within a specified time in an emergency after an upstream contactor has already disconnected a connection to a high-voltage battery. Other functions of the resistor chain include protecting the intermediate circuit capacitor in the event of overvoltage and, in conjunction with this, achieving a defined time constant when charging and discharging (e.g. τ = 5RC). Such behavior can delay a voltage rise when pulses occur and give control software sufficient time to intervene.

From the DE 10 2016 123 209 A1 a discharge device for an intermediate circuit is known, which has a positive voltage path and a negative voltage path, with a controllable switching element, which is coupled to the positive voltage path on the input side, and with a current limiter, which is coupled to an output terminal of the controllable switching element on the input side and which is coupled on the output side coupled to the negative voltage path. Furthermore, the present invention discloses an electrical intermediate circuit and a corresponding discharging method.

From the DE 10 2017 208 411 A1 a method and a control unit for limiting overvoltages due to an electrical load shedding during generator operation of a vehicle electrical system are known, the vehicle electrical system having: at least one battery, an intermediate circuit with an electrical energy store arranged therein and with a generator-operated e-machine connected to it and a contactor electrically connected between the intermediate circuit and the battery, which contactor was opened for load shedding, the intermediate circuit voltage present at the intermediate circuit being monitored, and the energy store being actively discharged when the intermediate circuit voltage exceeds a voltage threshold.

From the DE 10 2019 216 568 B3 a discharge device for an electric drive arrangement of a vehicle is known, with an input interface, with an output interface, with a main switching device, wherein the main switching device is connected to the input interface, with a first discharge branch, wherein a first input of the first discharge branch is connected to the main switching device , having a second discharge branch, and by a control device, the control device being designed to switch through the first discharge branch in a first discharge state of the discharge device and to switch through the second discharge branch in a second discharge state.

The invention is based on the object of creating a pulse-controlled inverter arrangement and a method for operating a pulse-controlled inverter arrangement in which, in particular, components can be saved.

The object is achieved according to the invention by a pulse-controlled inverter arrangement having the features of patent claim 1 and a method having the features of patent claim 9 . Advantageous configurations of the invention result from the dependent claims.

In particular, a pulse-controlled inverter arrangement is created, comprising a positive high-voltage input for supplying a positive line, a negative high-voltage input for supplying a negative line, a pulse-controlled inverter for providing at least one AC voltage from a DC voltage provided via the lines, at least one resistor arrangement between the positive line and the negative line with at least one Resistor, wherein the at least one resistor arrangement has at least one self-conducting semiconductor switch which is set up and arranged in such a way to close or disconnect an electrical connection formed between the positive line and the negative line via the at least one resistor arrangement, and a control device, wherein the control device for this purpose is set up, at least in a normal operating state, to turn off the at least one normally on semiconductor switch.

Furthermore, in particular a method for operating a pulse-controlled inverter arrangement is provided, with at least one resistor arrangement having at least one resistor between a positive line fed from a positive high-voltage input and a negative line fed from a negative high-voltage input being operated, with at least one normally on semiconductor switch of the at least one resistor arrangement for Closing or separating an electrical connection formed via the at least one resistor arrangement between the positive line and the negative line is operated, and the at least one self-conducting semiconductor switch is switched off by means of a control device of the pulse-controlled inverter arrangement at least in a normal operating state.

The pulse-controlled inverter arrangement and the method make it possible to increase energy efficiency in a normal operating state, since the at least one resistor of the at least one resistor arrangement is disconnected from the lines, so that no current can flow through the at least one resistor. This can prevent the occurrence of a power loss. This is achieved in that the resistor arrangement has at least one self-conducting semiconductor switch. The at least one normally on semiconductor switch is used to close or disconnect an electrical connection established via the at least one resistor arrangement between the positive line and the negative line. The at least one normally on semiconductor switch is controlled by a control device of the pulse-controlled inverter arrangement. In a normal operating state of the pulse-controlled inverter arrangement, the control device controls the at least one self-conducting semiconductor switch in such a way that it is blocked, that is to say non-conducting. In the normal operating state, there is therefore no power loss at the at least one resistor of the at least one resistor arrangement. In other words, no electrical energy is converted into heat without further use. However, if an error occurs, i.e. if the pulse-controlled inverter arrangement is not in the normal operating state, the control device no longer actively controls the at least one self-conducting semiconductor switch, so that it becomes conductive and an electrical connection between the positive line and the negative line via the at least one resistance is formed. The at least one resistor can then be used in particular to discharge an upstream intermediate circuit capacitor in an emergency, in particular after an upstream contactor has already disconnected a connection to a high-voltage battery, within a predetermined time. Furthermore, the at least one resistor can in particular protect the intermediate circuit capacitor in the event of overvoltage and, in particular in conjunction with this, can specify a defined time constant during charging and discharging (e.g. τ=5RC). Such behavior can, in particular, delay a voltage rise when pulses occur and give control software sufficient time to intervene. Since a self-conducting semiconductor switch is used, it is ensured that an electrical connection is formed even if the control device fails or the control fails.

By improving the energy efficiency, the pulse-controlled inverter arrangement and the method in particular also allow better use to be made of a battery charge. When used in a vehicle, a range can be increased as a result.

The at least one resistor arrangement can in particular have a plurality of resistors, in particular in the form of a resistor chain, that is to say in the form of resistors connected in series. For example, the resistor arrangement can have four resistors, in particular in the form of a resistor chain formed from the four resistors. In principle, however, a different number of resistors can also be provided.

A semiconductor switch is designed in particular as a metal-oxide-semiconductor field effect transistor (MOSFET). Self-conducting means, in particular, that the semiconductor switch is in a conducting state in which a current can flow between the source and drain contacts without an external drive, that is to say without a gate voltage being present. Self-locking means, in particular, that the semiconductor switch is in a non-conducting state without an external drive, that is to say without a gate voltage being present, in which no current can flow between the source and drain contacts. In principle, other semiconductor switches can also be used, provided they can be self-conducting or self-locking without external control.

A normal operating state is in particular an operating state of the pulse-controlled inverter and/or the pulse-controlled inverter arrangement and/or a device in or with which the pulse-controlled inverter arrangement is operated, in which operation is error-free.

The pulse-controlled inverter arrangement can additionally, in particular, also include an intermediate circuit capacitor. Furthermore, the pulse-controlled inverter arrangement can also in particular also provide means for providing intermediate voltages for the pulse-controlled inverter, for example in the form of a transformer with intermediate voltages that can be tapped off at the windings.

The pulse-controlled inverter arrangement can be used in particular in a vehicle, in particular in a motor vehicle.

Parts of the control device can be designed individually or combined as a combination of hardware and software, for example as program code that is executed on a microcontroller or microprocessor. It can However, it can also be provided that parts are designed individually or combined as an application-specific integrated circuit (ASIC) or field-programmable gate array (FPGA). However, it can also be provided that the control device is designed entirely or partially using analog circuit technology.

It is provided that the pulse-controlled inverter arrangement has at least one supply tap on the at least one resistor arrangement, the at least one supply tap being set up to supply gate drivers of the pulse-controlled inverter at least during a switch-on phase of the pulse-controlled inverter or to activate a supply. As a result, the gate drivers can be supplied during a switch-on phase without the need for additional components. By using at least part of the at least one resistor arrangement to supply the gate driver during the switch-on phase, components and installation space can be saved.

In one embodiment, it is provided that the control device is set up to process a number of input signals logically linked to one another and to no longer switch the at least one normally on semiconductor switch to blocking when at least one of the number of input signals meets a predetermined triggering criterion. As a result, states outside of the normal operating state can be detected using a number of input signals. In this case, the logical operation is selected and/or set up in such a way that the at least one self-conducting semiconductor switch always changes to the conducting state even if the logic and/or the control device fails.

In one embodiment, it is provided that the control device is set up to compare a voltage detected between the plus line and the minus line with an overvoltage threshold value and, when the overvoltage threshold value is reached or exceeded, to no longer turn off the at least one normally on semiconductor switch. As a result, an overvoltage across the at least one resistor of the at least one resistor arrangement, in particular via an RC element formed together with an intermediate circuit capacitor, can be specifically limited and/or reduced. As a result, the pulse-controlled inverter arrangement can be protected from damage.

It can be provided in a further development that the control device is set up to form and/or provide a hysteresis circuit, with the hysteresis circuit ensuring that after the overvoltage threshold value has been reached or exceeded that the at least one semiconductor switch is switched to the off state again after a predetermined reset voltage threshold has been undershot.

In one embodiment, it is provided that the control device is set up to actuate the at least one normally on semiconductor switch in a predetermined manner as a function of time, at least outside of the normal operating state. As a result, a load on the at least one resistor can be limited in time. As a result, the at least one resistor or the plurality of resistors can be designed to be smaller overall. This reduces costs and installation space (e.g. a required circuit board area). In particular, it can be provided that the at least one self-conducting semiconductor switch is driven in a pulsed manner in order to switch back and forth between a conducting and a blocking state.

In one embodiment it is provided that the pulse-controlled inverter arrangement comprises at least one further resistor arrangement between the positive line and the negative line and/or at least partially parallel to the at least one resistor arrangement with at least one resistor, the at least one further resistor arrangement having at least one self-locking semiconductor switch which is is set up and arranged in such a way as to close or disconnect an electrical connection formed via the at least one further resistor arrangement and/or at least partially via the at least one resistor arrangement between the positive line and the negative line, the control device also being set up to switch the at least one self-locking To control semiconductor switches at least outside of the normal operating state. This can improve the discharging of an intermediate circuit capacitor and possibly further capacitances, since a further path for discharging can be provided. This enables faster discharging of an intermediate circuit capacitance and any further capacitances that may be present. In particular, the number of resistors used for discharging can be increased, so that the individual resistors can be made smaller, which means that costs and installation space can be saved.

In one embodiment, it is provided that the control device is also set up to control the at least one normally on semiconductor switch and the at least one normally off semiconductor switch in such a way that these be switched to be conductive at a predetermined time. In particular, a load or an accruing power loss can be divided up as a result. As a result, the resistors can be made smaller, so that costs and installation space can be saved. In particular, it can be provided that the at least one normally on semiconductor switch and the at least one normally off semiconductor switch are alternately switched to a conductive state. This can be done in pulsed form in particular. In this case, for example, provision can be made for a power flow to be divided over time in a ratio of 50% to 50%. However, other ratios can also be provided, which can depend in particular on a number and design of the individual resistors in the at least one resistor arrangement and the at least one further resistor arrangement. However, it can be the case that the times during which the at least one normally on semiconductor switch and the at least one normally off semiconductor switch are conductive do not total more than 100%, which means that the semiconductor switches are switched conductive in particular alternately. In principle, however, a total of >100% is also possible.

In one embodiment it is provided that the control device uses and/or evaluates at least one of the following input signals as an input signal for controlling the at least one normally on semiconductor switch and/or the at least one further normally off semiconductor switch: a control signal from a controller of the pulse-controlled inverter, a control signal from a co- Controllers of the pulse-controlled inverter, a fail-safe output from a system basic chip of the pulse-controlled inverter with a watchdog function, an overvoltage detection signal and/or an accident signal (crash signal) from a vehicle controller. In principle, however, other input signals can also be used as an alternative or in addition.

A further embodiment provides that at least two input signals are used to control the at least one normally on semiconductor switch and/or the at least one further semiconductor switch. This allows redundancy to be created. It can then be possible, for example, to dispense with a co-processor, which means that costs and installation space can be saved.

In one embodiment it is provided that the pulse-controlled inverter arrangement comprises a switchable voltage measuring device arranged on the at least one resistor arrangement. This makes it possible to detect a voltage drop across the at least one resistor arrangement and to evaluate and use it for diagnostic purposes, for example. Switching on and off can take place, for example, by means of a semiconductor switch. By using at least part of the at least one resistor arrangement for voltage measurement, components can be saved, so that costs and installation space can be reduced.

Hierbei gibt die erste Zeile in jeder Spalte einzelne Schaltzustände des mindestens einen selbstleitenden Halbleiterschalters an („1“ = leitend). Die zweite Zeile gibt in jeder Spalte die einzelnen Schaltzustände der Zu- und Abschaltung der Spannungsmesseinrichtung an („1“ = zugeschaltet) und die dritte Zeile gibt an, ob bei korrekter Funktionsweise eine Spannung mittels der Spannungsmesseinrichtung erfasst wird oder nicht. Nur bei einer korrekten Funktionsweise darf die Spannungsmesseinrichtung eine Spannung erfassen (Eintrag in der dritten Zeile = „1“), das heißt nur, wenn der mindestens eine Halbleiterschalter leitend ist („1“) und die Spannungsmesseinrichtung zugeschaltet ist („1“). Die dritte Spalte entspricht diesem Zustand. Bei den drei anderen Kombinationen von Schaltzuständen des mindestens einen selbstleitenden Halbleiterschalters und der Zu- und Abschaltung der Spannungsmesseinrichtung darf hingegen keine Spannung erfasst werden (Spalten 1, 2 und 4, dort ist der Wert in der dritten Zeile „0“). Die Steuereinrichtung ist dann insbesondere dazu eingerichtet, das Vorliegen des jeweiligen Zustands der dritten Zeile der Plausibilitätsmatrix zu überprüfen, indem die Schaltzustände nacheinander spaltenweise gemäß dem jeweiligen Zustand in der ersten und der zweiten Zeile gesetzt werden und das Ergebnis einer Spannungsmessung anhand des zugehörigen Eintrags in der dritten Zeile überprüft wird (also: Spalte 1, dann Spalte 2, dann Spalte 3, dann Spalte 4). Die Reihenfolge, wie spaltenweise überprüft wird, kann hierbei auch anders sein.A further embodiment provides that the control device is set up to check a function of the at least one resistor arrangement by driving the at least one normally on semiconductor switch and driving and/or reading out the voltage measuring device. In this way, a plausibility can be checked in particular. For this purpose, in particular different switching states of the at least one self-conducting semiconductor switch and the connection and disconnection of the voltage measurement are activated in sequence. After the respective activation, it is checked in each case whether or not a voltage can be detected by means of the voltage measuring device. If the function is correct, the following plausibility matrix results, whereby an individual column of the matrix is considered during the plausibility check: $$\begin{array}{c}0110\\ 0011\\ 0010\end{array}$$

In this case, the first row in each column indicates individual switching states of the at least one self-conducting semiconductor switch (“1”=conducting). The second line in each column indicates the individual switching states of the switching on and off of the voltage measuring device ("1" = switched on) and the third line indicates whether a voltage is recorded by the voltage measuring device when it is functioning correctly or not. The voltage measuring device may only record a voltage if it is functioning correctly (entry in the third line = "1"), i.e. only if the at least one semiconductor switch is conductive ("1") and the voltage measuring device is switched on ("1"). The third column corresponds to this state. However, in the three other combinations of switching states of the at least one normally on semiconductor switch and switching the voltage measuring device on and off, no voltage may be recorded (columns 1, 2 and 4, where the value in the third row is "0"). The control device is then set up, in particular, to check the presence of the respective status of the third row of the plausibility matrix by setting the switching statuses one after the other in columns according to the respective status in the first and second row and the result of a voltage measurement based on the associated entry in the third line is checked (i.e.: column 1, then column 2, then column 3, then column 4). The order in which columns are checked can also be different.

In particular, a vehicle is also created, comprising at least one pulse-controlled inverter arrangement according to one of the described embodiments. The vehicle is in particular a motor vehicle, in particular a hybrid or electric vehicle. In principle, however, the vehicle can also be another land, water, rail, air or space vehicle, for example a drone or an air taxi.

Further features for the configuration of the method result from the description of configurations of the pulse-controlled inverter arrangement. The advantages of the method are in each case the same as in the configurations of the pulse-controlled inverter arrangement.

• 1 eine schematische Darstellung einer Ausführungsform der Pulswechselrichteranordnung;
• 2 eine schematische Darstellung einer logischen Verknüpfung zur Ansteuerung des selbstleitenden Halbleiterschalters;
• 3 eine schematische Darstellung einer weiteren Ausführungsform der Pulswechselrichteranordnung;
• 4 eine schematische Darstellung einer logischen Verknüpfung zur Ansteuerung eines selbstsperrenden Halbleiterschalters einer Ausführungsform der Pulswechselrichteranordnung;
• 5 eine schematische Darstellung von weiteren Ausführungsformen der Pulswechselrichteranordnung.

The invention is explained in more detail below on the basis of preferred exemplary embodiments with reference to the figures. Here show:

• 1 a schematic representation of an embodiment of the pulse-controlled inverter arrangement;
• 2 a schematic representation of a logical operation for driving the normally on semiconductor switch;
• 3 a schematic representation of a further embodiment of the pulse-controlled inverter arrangement;
• 4 a schematic representation of a logic operation for driving a self-locking semiconductor switch of an embodiment of the pulse-controlled inverter arrangement;
• 5 a schematic representation of further embodiments of the pulse-controlled inverter arrangement.

In 1 a schematic representation of an embodiment of the pulse-controlled inverter arrangement 1 without a supply tap is shown. In particular, provision can be made for the pulse-controlled inverter arrangement 1 to be arranged and used in a vehicle 50 .

The pulse-controlled inverter arrangement 1 comprises a positive high-voltage input 2+ for supplying a positive line 3+ from a battery B, which can be separated via a contactor (not shown), a negative high-voltage input 2- for supplying a negative line 3-, which can also be separated via a contactor (not shown). Battery B, a pulse-controlled inverter 4 for providing at least one AC voltage from a DC voltage provided via lines 3+, 3-. The pulse-controlled inverter 4 provides a three-phase rotary field for an electrical machine M in the illustrated embodiment. For this purpose, the pulse-controlled inverter 4 is supplied with the direct voltage which is provided by the lines 3+, 3-. Intermediate voltages, which are provided, for example, by a transformer (not shown) with intermediate taps, supply logic and drive voltages from gate drivers of pulse-controlled inverter 4.

The pulse-controlled inverter arrangement 1 has a resistor arrangement 6 between the positive line 3+ and the negative line 3-. In the example shown, the resistor arrangement 6 has four series-connected resistors R1, R2, R3, R4. A normally on semiconductor switch 7, for example a normally on MOSFET, is arranged between the resistors R1, R2, R3, R4 and the positive line 3+ or between the resistors R1, R2, R3, R4 and the negative line, with only one of the two possibilities being formed in each case is. By means of the normally on semiconductor switch 7, an electrical connection formed between the positive line 3+ and the negative line 3- via the at least one resistor arrangement 6 can be closed or opened.

The self-conducting semiconductor switch 7 is controlled by a control device 8 via a gate contact. The control device 8 is set up to turn off the normally on semiconductor switch 7 at least in a normal operating state in which there is no error. This separates the electrical connection of the series-connected resistors R1, R2, R3, R4 from the positive line 3+ or the negative line 3-, so that no (loss) power can flow through the resistors R1, R2, R3, R4 . In a state outside of the normal operating state, for example a fault state in which an electrical connection between a battery B and the high-voltage inputs 2+, 2- has already been separated, in particular by means of a contactor (not shown), the normally on semiconductor switch 6 is either switched off by actively switching off a gate voltage by means of the control device 8 or passively by switching off the gate voltage so that an electrical connection is formed between the resistors R1, R2, R3, R4 of the resistor arrangement 6 and an intermediate circuit capacitance C (and any other capacitances present) are discharged in a controlled manner can.

It can be provided that the control device 8 is set up to direct the self to drive the semiconductor switch 6 in a predetermined manner as a function of time, at least outside of the normal operating state. For example, a pulsed control can take place, in which the self-conducting semiconductor switch 6 is switched on or off in a pulsed manner.

In 2 is a schematic representation of a logic operation 9-1 for driving the self-conducting semiconductor switch 7 ( 1 ) shown. Provision is made for the control device to be set up to process a plurality of input signals 10-1, 10-2, 10-3 in a logically linked manner and to switch the self-conducting semiconductor switch 7 ( 1 ) is no longer switched to blocking when at least one of the plurality of input signals 10-1, 10-2, 10-3 meets a predetermined triggering criterion. The self-conducting semiconductor switch 7 is controlled via a correspondingly provided signal at the output 13.

In particular, it is provided that the control device is set up to compare a voltage detected between the positive line and the negative line with an overvoltage threshold value and, when the overvoltage threshold value is reached or exceeded, the at least one normally on semiconductor switch 7 ( 1 ) can no longer be switched blocking. In the illustration shown, such an overvoltage detection 11 supplies the input signal 10-1.

The input signal 10-2 can, for example, come from a controller 12 of the pulse-controlled inverter 4 ( 1 ) to be delivered. For example, an operating state of the controller 12 can be provided by means of the input signal 10-2. Further input signals 10-3 can be provided by various devices, for example by an accident detection system 26.

In the example shown, the logical link 9-1 includes an operational amplifier, two NOR gates and a NAND gate, but can in principle also be designed differently depending on the application.

The one in the 2 The logical link 9-1 shown is merely an example and can in principle also be configured differently.

In 3 a schematic representation of a further embodiment of the pulse-controlled inverter arrangement 1 without a supply tap is shown. The pulse-controlled inverter arrangement 1 is basically like that in FIG 1 Formed embodiment shown, the same reference numerals denote the same features and terms.

In the embodiment shown, it is additionally provided that the pulse-controlled inverter arrangement 1 comprises a further resistor arrangement 14 between the plus line 3+ and the minus line 3- and/or at least partially parallel to the at least one resistor arrangement 6. In the embodiment shown, the further resistor arrangement 14 comprises three series-connected resistors R20, R21, R22. In this example, the further resistor arrangement 14 also has a normally-off semiconductor switch 15 (in principle, the normally-off semiconductor switch 15 can also be arranged on the side of the negative line 3-), which is set up and arranged in such a way that a via the further resistor arrangement 14 and/or to close or disconnect at least partially the electrical connection formed between the positive line 3+ and the negative line 3- via the resistor arrangement 6. The control device 8 is also set up to activate the self-locking semiconductor switch 15 at least outside of the normal operating state.

In particular, the further resistor arrangement 14 in the example shown is electrically connected to a tap 16 between the resistors R1 and R2 of the resistor arrangement 6 and to the negative line 3-. The tap 16 is electrically connected to the normally-off semiconductor switch 15, and the normally-off semiconductor switch 15 is connected to the resistors R20, R21, R22. In principle, however, the further resistor arrangement 14 can also be configured differently and electrically contacted.

To control the normally-on semiconductor switch 7 (here connected to the negative line 3, for example) and the normally-off semiconductor switch 15, the control device 8 has modules 8-1, 8-2, for example, in which, in terms of signals, there is a logical combination for driving the semiconductor switches 7, 15 is trained.

It can be provided that the control device 8 is also set up to control the normally on semiconductor switch 7 and the normally off semiconductor switch 15 in such a way that they are switched to the on state in a time-specified manner. In particular, the control device 8 can alternately turn on the semiconductor switches 7, 15 in a pulsed manner. A load on the individual resistors Rx can be reduced as a result.

In 4 is a schematic representation of a logic operation 9-2 for driving the normally-off semiconductor switch 15 ( 3 ) shown. It is provided that the module 8-2 of the control device 8 ( 3 ) is set up to to process a plurality of input signals 10-1, 10-2, 10-3, 10-4, 10-5 logically linked to one another and the self-locking semiconductor switch 15 ( 3 ) head for.

It can be provided that the control device 8 ( 3 ) uses and/or evaluates at least one of the following input signals 10-x as input signal 10-x for controlling the at least one normally on semiconductor switch and/or the further normally off semiconductor switch 15: a control signal from a controller 17 of the pulse-controlled inverter, a control signal from a co-controller 18 of the pulse-controlled inverter, a fail-safe output 19 from a system basic chip with a watchdog function, an overvoltage detection signal 20 and/or an accident signal 21 of a vehicle controller of a vehicle. In the example shown, the logical operation 9-2 includes NOR gates, but can in principle also be designed differently depending on the specific application.

In a further developing embodiment it is provided that at least two input signals 10-x for controlling the self-conducting semiconductor switch 7 and/or the further semiconductor switch 15 ( 3 ) be used. This allows resources to be saved elsewhere. For example, a co-controller 18 of the pulse-controlled inverter can be saved by such an increased redundancy.

In 5 a schematic representation of further embodiments of the pulse-controlled inverter arrangement 1 is shown. The pulse-controlled inverter arrangement 1 is basically like that in FIG 1 or 3 Formed embodiments shown, the same reference numerals denote the same features and terms. In this case, the embodiment shown can also be formed without the further resistor arrangement 14 . The arrangement of the normally on semiconductor switch 7 and the normally off semiconductor switch 15 can also be fundamentally different; in particular, they can also be arranged on the minus side (cf. e.g 1 ).

In the embodiment shown, the pulse-controlled inverter arrangement 1 has a connectable voltage measuring device 22 arranged on the resistor arrangement 6 . In the embodiment shown, the voltage measuring device 22 comprises a diode 23 serving as reverse polarity protection, which is connected to a voltage tap 24 between the resistors R3, R4 and an emitter of a bipolar transistor 25. The collector of the bipolar transistor 25 is connected to the resistors R10, R11, which are connected in series to GND of a low-voltage supply. A base of the bipolar transistor 25 is controlled by means of a module 8-3 of the control device 8 provided for this purpose. After the bipolar transistor 25 (and the normally on semiconductor switch 7) has turned on, a voltage drops across the resistor R11. The voltage across resistor R11 is sensed for diagnostic purposes.

In a further development, it can be provided that the control device 8 is set up to check a function of the resistor arrangement 6 by activating the normally on semiconductor switch 7 and activating and/or reading out the voltage measuring device 22 . For this purpose, a predetermined plausibility matrix of switching states is checked in particular. For this purpose, in particular different switching states of the normally on semiconductor switch 7 and the switching on and off of the voltage measurement 22 taking place via the bipolar transistor 25 are activated in succession. After the respective activation, it is checked in each case whether or not a voltage can be detected by means of the voltage measuring device 22 . If the function is correct, the following plausibility matrix results: $$\begin{array}{c}0110\\ 0011\\ 0010\end{array}$$

Columns in the first row indicate the possible switching states of the normally on semiconductor switch 7 (“1”=conductive). Columns in the second line indicate the possible switching states of the bipolar transistor 25 (“1”=conductive). The third line indicates in columns whether a voltage is expected ("1") or not. Correct functioning, i.e. plausibility, is now checked by column-by-column setting of the switching states on the normally on semiconductor switch 7 and the bipolar transistor 25 and comparing the subsequent voltage measurement (voltage measured or not). A voltage may drop across the resistor R11 only when both the normally on semiconductor switch 7 and the bipolar transistor 25 are switched on (cf. column 3), otherwise not.

It is provided that the pulse-controlled inverter arrangement 1 has a supply tap 27 on the resistor arrangement 6, the supply tap 27 being set up to supply gate drivers of the pulse-controlled inverter 4 at least during a switch-on phase of the pulse-controlled inverter 4 via a transformer 5 or to activate a supply. In the example shown, the supply tap 27 is located between the resistors R2, R3 of the resistor arrangement 6. In principle, however, the supply tap 27 can also be arranged somewhere else.

In addition to an increase in energy efficiency due to a reduced power loss, components can also be saved with the pulse-controlled inverter arrangement 1 described in this disclosure, so that costs and installation space can be saved.

The method for operating a pulse-controlled inverter arrangement 1 is carried out in particular using one of the described embodiments.

Reference List

1

PWM inverter arrangement

2+

positive high voltage input

2-

negative high voltage input

3+

positive line

3-

negative wire

4

pulse inverter

5

transformer

6

resistor assembly

7

self-conducting semiconductor switch

8th

control device

8-1

module

8-2

module

8-3

module

9-1

logical connection

9-2

logical connection

10-x

input signal

11

overvoltage signal

12

controllers

13

Exit

14

further resistance arrangement

15

self-locking semiconductor switch

16

tap

17

controllers

18

co-controller

19

Fail safe output

20

overvoltage detection signal

21

accident signal

22

voltage measuring device

23

diode

24

voltage tap

25

bipolar transistor

26

accident detection

27

supply tap

50

vehicle

B

battery

C

intermediate circuit capacity

M

electric machine

Rx

Resistance

Claims (9)

Pulse-controlled inverter arrangement (1), comprising: a positive high-voltage input (2+) for supplying a positive line (3+), a negative high-voltage input (2-) for supplying a negative line (3-), a pulse-controlled inverter (4) for providing at least one alternating voltage a DC voltage provided via the lines (3+,3-), at least one resistor arrangement (6) between the positive line (3+) and the negative line (3-) with at least one resistor (Rx), the at least one resistor arrangement (6) has at least one normally on semiconductor switch (7) which is set up and arranged in such a way to close or disconnect an electrical connection established via the at least one resistor arrangement (6) between the positive line (3+) and the negative line (3-), and a control device (8), wherein the control device (8) is set up to, at least in a normal operating state, the at least one self-conducting Semiconductor switch (7) to be turned off, characterized by at least one supply tap (27) on the at least one resistor arrangement (6), the at least one supply tap (27) being set up to gate drivers of the pulse-controlled inverter (4) at least during a switch-on phase of the pulse-controlled inverter ( 4) to supply or activate a supply. Pulse-controlled inverter arrangement (1) after claim 1 , characterized in that the control device (8) is set up to process a plurality of input signals (10-x) logically linked to one another and to no longer switch the at least one self-conducting semiconductor switch (7) to be blocked if at least one of the plurality of input signals (10- x) meets a specified triggering criterion. Pulse-controlled inverter arrangement (1) after claim 1 or 2 , characterized in that the control device (8) is set up to a between the positive line (3 +) and the negative line (3-) detected voltage with a Comparing the overvoltage threshold and no longer blocking the at least one normally on semiconductor switch (7) when the overvoltage threshold is reached or exceeded. Pulse-controlled inverter arrangement (1) according to one of the preceding claims, characterized in that the control device (8) is set up to actuate the at least one normally on semiconductor switch (7) in a predetermined manner as a function of time at least outside the normal operating state. Pulse-controlled inverter arrangement (1) according to one of the preceding claims, characterized by at least one further resistor arrangement (14) between the positive line (3+) and the negative line (3-) and/or at least partially parallel to the at least one resistor arrangement (6) with at least one Resistor (Rx), the at least one further resistor arrangement (14) having at least one self-locking semiconductor switch (15) which is set up and arranged in such a way that a via the at least one further resistor arrangement (14) and/or at least partially via the at least one resistance arrangement (6) between the positive line (3+) and the negative line (3-) to close or disconnect the electrical connection formed, the control device (8) also being set up to switch the at least one self-locking semiconductor switch (15) at least outside the normal control operating status. Pulse-controlled inverter arrangement (1) according to one of the preceding claims, characterized in that the control device (8) for controlling the at least one normally on semiconductor switch (7) and/or the at least one further normally off semiconductor switch (15) receives at least one of the following input signals (10-x ) uses and/or evaluates: a control signal from a controller (17) of the pulse-controlled inverter (4), a control signal from a co-controller (18) of the pulse-controlled inverter (4), a fail-safe output (19) from a system basic chip of the Pulse-controlled inverter (4) with a watchdog function, an overvoltage detection signal (20) and/or an accident signal (21) from a vehicle controller. Pulse-controlled inverter arrangement (1) according to one of the preceding claims, characterized by a switchable voltage measuring device (22) arranged on the at least one resistor arrangement (6). Pulse-controlled inverter arrangement (1) after claim 7 , characterized in that the control device (8) is set up to check a function of the at least one resistor arrangement (6) by activating the at least one normally on semiconductor switch (7) and activating and/or reading out the voltage measuring device (22). Method for operating a pulse-controlled inverter arrangement (1), wherein at least one resistor arrangement (6) with at least one resistor (Rx) is operated between a positive line (3+) fed by a positive high-voltage input (2+) and a negative line (3-) fed by a negative high-voltage input (2-), wherein at least one normally on semiconductor switch (7) of the at least one resistor arrangement (6) is operated to close or disconnect an electrical connection established via the at least one resistor arrangement (6) between the positive line (3+) and the negative line (3-), and wherein the at least one normally-on semiconductor switch (7) is turned off by means of a control device (8) of the pulse-controlled inverter arrangement (1), at least in a normal operating state, characterized in that at least one supply tap (27) on the at least one resistor arrangement (6) supplies gate drivers of the pulse-controlled inverter (4) at least during a switch-on phase of the pulse-controlled inverter (4) or a supply is activated.

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